Document top issues and process for converting from HTML --> AMP HTML

Create a guide that:

- Identifies top issues for converting a website from HTML to AMP, include resolutions
- Identifes common process for converting
- Identifies tips/gotchas + tools
- Integrates this video - https://www.youtube.com/watch?v=OO9oKhs80aI&t=0s&index=4&list=PLXTOW_XMsIDTIRIu4Af-bqfGkUhPSE75A

Start by reviewing the issue requirements and the linked conversion video. Identify the guide's location in the amp.dev documentation structure, then organize coverage of HTML-to-AMP issues and resolutions, the conversion process, tips, gotchas, and tools. Done means a complete, discoverable guide that integrates the video.

Written by the indexing model from the issue text.